The subject matter herein relates in general to safety devices and systems for providing protection against high energy shock loads, and in particular relates to safety devices which may be used in a vehicle for protecting an occupant disposed therein against compressive forces attributed to instantaneous, high-rate vehicle accelerations.
Instantaneous accelerations in the field encompass any event resulting in a high energy impulse imparted to a vehicle, such as may occur for example in a so-called “slam down” typically associated with a helicopter crash, or explosive events such as an under-vehicle mine blast. The resulting acceleration may involve the entire vehicle, or some portions of the vehicle to a greater degree than others. For example, an improvised explosive device may have an approximate fragment velocity of 950 m/s, which, when impacting a vehicle's outer surface, may cause significant localized deformation. Thus, in addition to acceleration of the vehicle as a whole, inward deformation of the vehicle itself also poses a threat to occupants situated therein.
Accordingly safety devices within the field may comprise devices intended to mitigate or reduce the amount of energy that is transmitted from the vehicle or from certain portions of the vehicle to the occupants. In particular, such safety devices may include those intended to reduce the amount of impact energy imparted through a seat to the torso and spine of a seated occupant.